Plasma levels of triglycerides (TG) increase, then decrease with advancing age. In addition plasma TG is known to increase following acute ethanol administration. The clearance of circulating lipoprotein triglyceride is thought to be mediated primarily by lipoprotein lipase. This enzyme activity is present in hepatic as well as a number of extrahepatic tissues and is released into the plasma after heparin administration. Post heparin lipolytic activity (PHLA) has been used to assess the activity of lipoprotein lipase. A method is now available to distinguish extrahepatic (protamine-inactivated or PI) from hepatic (protamine-resistant or PR) PHLA. The purpose of this project is to examine the effect of age PHLA and the effect of acute ethanol administration on PHLA in an effort to increase our understanding of the mechanism by which plasma TG changes with age and under the influence of ethanol.